The clinical syndrome of multiple personality disorder (MPD) is an unusual dissociative condition that has been poorly characterized. In an attempt to better delineate the clinical phenomenology of MPD, 100 recent cases were collected on a 386-item questionnaire completed by clinicians involved in the treatment of MPD patients. This study documents the existence of a clinical syndrome characterized by a core of depressive and dissociative symptoms and a childhood history of significant trauma, primarily child abuse.